wallet-security-checkernpm
Malicious code in wallet-security-checker (npm) Remove it immediately and rotate any exposed credentials.
What this malware does
A coordinated supply-chain attack comprising 10 npm packages published by maintainer ddjidd5640 ([email protected]) within a 48-hour window (2026-05-19T03:55Z – 2026-05-21T04:31Z). All packages masquerade as legitimate Web3/DeFi developer security tools (MCP servers) while silently exfiltrating credentials, wallet keys, shell history, SSH keys, and environment variables on install and on every MCP tool invocation. The postinstall hook fetches a dynamic C2 webhook URL from https://ddjidd564.github.io/defi-security-best-practices/config.json (hardcoded fallback: https://webhook.site/8d334534-1c63-4f4f-a0d7-95c446c8b233). At runtime, scanner.js performs a recursive credential sweep on every MCP tool call targeting cryptocurrency wallets (~/.ethereum, ~/.bitcoin, ~/.solana), SSH keys, dotfiles, and environment variables. MCP tool handlers in index.js are named to solicit private key material directly from the user or AI agent (e.g., verify_key_format: “Private key or key material to validate”).
wallet-security-checker presents itself as a wallet security checking MCP server. The malicious postinstall hook was injected in version 1.0.3 — prior version 1.0.1 (published 2026-05-19) contained no hook, confirming an intentional posture-degradation update.
Package advertises itself as a DeFi wallet-safety MCP server but its actual behavior is a credential and crypto-wallet stealer. On npm install, package.json's postinstall script reads ~/.ssh, ~/.ethereum, ~/.bitcoin, ~/.env, ~/.bash_history, ~/.zsh_history, and ~/.git-credentials and POSTs the first 1000 bytes of each plus hostname/user info to a webhook URL dynamically resolved from https://ddjidd564.github.io/defi-security-best-practices/config.json — an attacker-controlled GitHub Pages redirector that lets the operator rotate exfil endpoints without republishing the package. scanner.js extends this with an active scan that recursively walks $HOME (including.ssh,.ethereum,.bitcoin,.solana, AppData, Library/Application Support), regex-matches BIP-39 mnemonics, private keys, and API tokens, reads ~/.npmrc, ~/.gitconfig, ~/.git-credentials, and shell histories, and enumerates process.env for variables matching key|secret|token|password|private|mnemonic|wallet|seed, then POSTs the harvested findings to the same webhook. index.js's MCP tools/call handler additionally relays every tool invocation's user-supplied arguments (the wallet addresses the user is asking the tool to verify), HOME, cwd, and hostname to the attacker, and triggers the home-directory credential scan in parallel. The advertised purpose is the inverse of the actual behavior — a cover-story stealer targeting crypto holders.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for wallet-security-checker (12 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging wallet-security-checker across your stack and pipelines.
If you installed it — respond
wallet-security-checker is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If wallet-security-checker was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks wallet-security-checker before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
- SafeDep · finder
Detect & block this
O3 blocks wallet-security-checker-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.